Gamo Shadow won't cock

[John D-H]

I have a Gamo Shadow air rifle.  It is 4 years old and I've shot about 3,300 pellets through it.
It suddenly stopped cocking.  I can break the barrel, and the resistance is the same, but it won't cock once the barrel is fully pulled.  

I did take the barrel assembly off the stock and wiped away some of the dirt.  I reassembled it and it worked again for about 100 more shots.  
And then the same problem; it would not cock again.  

I don't know what could be wrong or what I did to cause the temporary fix.  Any ideas?
I appreciate any advice or help.  

[gamo2hammerli]

3,300 shots.....that's alot of shots. Have you ever changed the main spring? Average spring life would be between 2,000 to 4,000 shots (Personal experience). When a spring breaks....the small piece(s) usually end up inside the long piece....sometimes you can still shoot (Less power and you won't know about it unless you're shooting at really far away objects)....and sometimes the spring binds up. Seems that's what's happening with your Shadow. You can break and cock the barrel....but just missing a few millimeters to catch on the sear.

When you took the receiver off the stock....you probably jiggled the broken piece loose, therefore you were able to put a few shots through the gun. I had that happen with my Gamo Viper. The spring in my Big Cat broke in two different places...I didn't notice the power drop and didn't even know the spring had broken until it wouldn't catch when breaking the barrel.

Here's a photo of my Crosman Sierra Pro's spring in four pieces....it was still shooting after the third piece broke but I noticed a huge power drop. That's when I opened her up to check....and all the small pieces were inside the long piece.

Btw, a BIG WELCOME to the GTA forum and family.

[ezman604]

Hmmm....the way I read it is it's not catching when cocked. The sear is not engaging. Sounds like a spring has broken (or just come out of place) in the trigger group or the sear has worn or broken. I would pull the trigger group for an inspection, and check out the main spring while you're in there. OF COURSE do not attempt this unless you have a spring compressor.

Happy Shooting!!!!

Dave

[John D-H]

Thanks very much for the welcome, help, and photos.  
This sounds like perhaps the spring broke.  When I shot it after reassembly it seemed just a little easier to cock.  
Tearing the gun apart is probably beyond my gunsmithing capabilities and I don't have a spring compressor.
I will look into either replacing the gun or getting it finely repaired and tuned.  
John D-H

[gamo2hammerli]

John, I always thought of myself as not too good with my hands.....but I've changed 5 springs in my airguns.  There's some video on youtube showing how it's done, and on Pyramid Air Guns' blog, B.B Pelletier/Tom Gaylord describes how to take apart and lube a springer.  It's a 13 parter (Easy read) written about a few years back.

Search the site here....there's a few very well build compressors....you can build one easily.

[snookman]

Good morning John D-H and welcome to the GTA. Check out this link  http://www.network54.com/Forum/79574/thread/1257146873/FS-++Spring+Compressor  it looks like it's a well made product and as soon as I can afford it I will get one myself,but if you want to send the gun to an Airgunsmith,check out Gene's tunez & toys in the GTA mall.I beleve it will be cheaper to have the gun tuned and repaired than to buy a new gun. Good luck,snookman

[ezman604]

Yep, that's an excellent spring compressor. Tim makes a good product and an excellent price. If you don't want to attempt it yourself, I highly recommend sending it in to Gene at Gene's Tunez & Toyz for a Turbo Tune. He will replace the spring, seal and touch up the trigger. You will see an amazing difference and will have a sweet shooter when you get it back. The cost works out to roughly the same for either way you go but you will save a little doing it yourself. But the difference is WELL worth it when Gene works his magic.

Try this. If the gun is STILL not cocking, try putting a finger behind the trigger and putting a little pressure on it to push it forward. Break the barrel and attempt to cock it. See if you feel the trigger bump and move slightly forward.Does the gun stay cocked? If you feel no movement or bump through the trigger and you cycle the barrel all the way back, I would say you have a trigger group problem as I stated earlier. If you have a broken mainspring, a dislodged piece MAY also be keeping the piston from moving all the way back to latch the sear. A disassembly is definately needed to see just what's going on.

Keep us informed on your progress.

Welcome & Happy Shooting!!!!

Dave